Motor-starting rheostat.



I PATENTED J AN. 1, P.H. ZIMMER. MOTOR STARTING RHEOSTAT.

APPLIGATION. FILED JUNE 28.1905.

Witnesses.-

To all whom it may concernr Pit-UL H;

ZIMMER, OF SCHENEOTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC OOMPANY, A CORPORATION OF NEW YORK.-

" MOTOR-STARTING RHEOSTAT.

Specification of Letters Patent.

Patented Jan. 1,1907.

I Application filed June 28,1905. Serial No. 267.367-

; Be it known that 1, PAUL H. ZIMMER, a acitizen of the United States, residing at ostats, of w Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Motor-StartingRhehich the following is a specifica- This inventionrelates to devices for con trolling motor circuits, and has for its object the provision of a device of this character I which cannot be destroyed by the careless motor-starting rheostats. kind, asis well known, the circuit is first closed through a starting-resistance, which is [gradually out out as the motor speeds up i handling of an operator, which is simple of -construction, inexpensive to manufacture, l5;

3? :cient.

and is at the same time durable andeflie More specifically, my invention relates to In devices of this until all of the resistance is short-circuited.

It has been the common practice hcrotoforeto maintain the controlling-arm in the'short- ;.circuited position by means of aTno-voltage magnet, so that upon failure of voltage the arm which s biased to starting position. is

. motor-armature.

released and flies back'to the ofi position,

so that upon the return of voltage the protecting resistance will be in series with the Such a construction has the disadvantage that. the resistance contact-sheds are burned when the circuit opens and the arm fl es back to its oil position.

i carrying out my invention I also proy de a controlling-arm blased to the starting position; but I further provide means where- 'by the controlling-arm. will return to the oil I positionas soon as the normal running conditions are established, therebypreventing T he motor is My invention further consists in, the details of construction and the arrangement and oonibination of elements hereinafter seti forth, and particularly pointed out in the j claims appended ,to-and forming a part oi" this application.

The single figure of drawing is a plan view o'l' aistarting rheostat embodying my im- Q proveinents.

Referring to the drawing, 1 is an insulating-base of slate or soapstone, having mounted thereon the starting-studs 2, forming the terminals of starting-resistances 3. A lever or controlling arm 4 is pivoted at' 5, so that its free end, which is provided with a handle 6, may be movedover and. successively en gage the starting-Studs 2 inthe usual manner. A. spring 7 gives the startingarm a bias to the oil position, as shown in the drawing.

A magnet 8, provided with two windings 9 and 10, controls an armature 11, carrying a bridging contact 12. When the magnet S is suliiciently energized, the armature i1 is drawn up so to bridgethe contacts 13 14, which closes a shuntcircuit around thestartingarm, as hereinafter set forth. The magnet S normally energized by the winding ll), the

circuit of which independent of the con; trolling-arm; but the energization, however, is not su'llicie'nt to attract the armature to bridge the contacts. The other winding 9 nmstbeenergizedincoulcr-to accomplish this result. 'llmcircnitol this winding, however, is not closed until the starting-arm is moved to the last stud and all oi the starting-insistance thereby cut out. in this position the starting-arm engages, by means of a contactor 15, with the stud 16, to which one end of the winding 9 connected. A circuit is thus established through windin 9, which is in parallel with the winding ll). lhc magnet 8 being sullicionll energized ther upon draws up the armature 11/ bridges the con tacts 13 1,4, and completes 'a shunt-circuit around the starting-arm. Upon being released the arm returns to'its starting position, brenking the circuit of winding 9; but the slnint-c rcuit.is maintained, since the single winding is sullicient to maintninit, Upon failureol voltage the armature will drop and break the slmnt-circuit, and the motor cannot be again started without repeating theoperation above described.

in order to protect in) device against overloads, l. have provided :1 circuil hrculwr comihe arrangement of circuits is as follows: I Upon moving the controlling-arm onto the first startingstud the current passes from lead 22 to clip 19, through lever 17 to mag- I net 20, thence to the pivot 5, arm 4, startingresistance 3, conductors 23 .24 to motor-armature and back to line. The field-curi rent passes from pivot 5 throughconductor I 26, field 27, back to the line at A branch I circuit passes from pivot 5, through conductor to winding of the magnet 8 and thence by conductor back to the line at 31. When. I the starting-arm reaches the last stud, the" circuit of the winding 9 is completed from I pivot 5 through arm 4, contactor 15, stud 16, i conductor 32, to winding 9, thence back to I line through conductor 30. The magnet 8 is now sull'iciently energized to draw up its armature and bridge the contacts 13 14. The I circuit through the motor will now be asfol- I lows; from. lead 22, through the ciruit- I breaker'to pivot 5, thence through conduc- I tors 29 and. 33, to contact 13, bridge 12, (3011- I tact 1'4, and conductor 24: to the motor-an I mature 25, and back to line. A shunt is thus I closed around the arm 4, so that the operator I may release the handle, allowing the arm to return to starting position to he in readiness I to start again, broken by the return of the arm, but the winding 10, which is always in circuit as long as the circuitdn'eaker is closed, is snllicient to maintain the closed condition of the shunt. I Upon overload the motor-circuit will he broken at the circuit-l)rcaker, and upon fail- I ure of voltage, due to the opening ol" the circuit-brealrer or to other causes, the bridgingcontact 12 will drop and break t. shunt-cir- I c'uit, lVhcn the circuit-breaker is open, in order to start the motor the starting-arm is I first moved to the left. until the lug 3-1engages the lever 17 to close the same. The arm is I then moved to the right, as hereinhetore described. I

l I I I I I What 1 claim as new, and desire to secure by Letters Patent of the Unitedfitates, s

1. in a starting-1heostat, the combination with a. controlling member having a bias to the starting position, of electrically -controlled means For closing an auxiliary circuit around said arm when the latter running position .ln a star-tingaheostat, the comb nation with a. controlling-arm having a. bias to the starting position, of electrically-controlled means for closing a shunt-circuit around said arm when the latter is moved to running po- I sition and. for niaintaining it closed when the I arm is returned to starting position. l

3. lln a starting-rheostat, the combination I with a pivoted'controlling-arm having a bias I to the starting posit-ion,' of means for closing I is moved to The circuit of winding 9 is I a shunt-circuit around said arm when the latter is moved to running position, said means including maintaining it closed when the arm is returned to starting position.

- 4. In a starting-rheostat', the combination with a pivoted controllingerm having shirts to the starting position, of a switch, an electromagnet for operating the same to close a. shunt-circuit around said arm when the latter is moved to running position, said magnet being normally energized sufficiently to maintain said shunt-circuit.

5. In a starting-rheostat, the combination with a pivoted controlling-arm having a bias to the starting position, of a switch, a compound-wound electromagnet for operating the same to close a shunt-circuit around said arm when the latter is moved to runningposition, said magnet being normally energized electromagnetic means, for

sulliciently by one of its windin s to main-'- tain the closed condition of sai shunt-circuit.

6. A 1notor-rheostat comprising a variable resistance, a controlling-arm therefor, and

I eleetrically-controlled means for closing an auxiliary circuit around said arm when the latter is moved to a predetermined position when the arm and for maintaining it closed leaves said position.

7. A motor-starter comprising a spring-retracted starting-lever, a startingeresistance cooperating therewith, an eleetromagnet, a circuit-breaking relay cut in by said magnet when the lever is moved to full on position, and means dependent upon line-voltage for maintaining the relay active.

8. A starting-rheostat comprising a switch biased to open position, a resistance-controlling arm arranged to close said switch when moved in the direction to insert resistance, means responsive to normal circuit conditions for holding said switch closed, and means for closing an auxiliary circuit around said controlling-arm when the latter is moved to running position.

9. A starting-rheostat comprising a springactuated switch,a locking device for holding said switch in closed position, means responsive to overload conditions for releasing said device, a resistance-controlling arm, and an PAUL H; ZIMME R.

\Vitn ess es BENJAMIN B. HULL, HELEN ()Rrolro. 

